v0.1.0

Initial release. Lugiato-Lefever steady states (exact Kerr and linear-plus-pump split steps), linearized Bogoliubov fluctuation matrix around arbitrary steady states with a stability guard, and detected quadrature-noise spectra through input-output theory for an extraction port plus intrinsic loss. The test suite reproduces the closed-form degenerate-parametric-oscillator spectrum to 1e-10 and recovers the 3 dB extraction limit at critical coupling from the machinery itself. Photonic-molecule extraction is the v0.2 roadmap. Test suite (7 tests) runs on CI.